def get_execv_args(self):
"""Internal: turn a program name into a file name, using $PATH,
make sure it exists / is executable, raising a ProcessException
if not """
try:
commandargs = shlex.split(self.config.command)
except ValueError as e:
raise BadCommand("can't parse command %r: %s" % \
(self.config.command, str(e)))
if commandargs:
program = commandargs[0]
else:
raise BadCommand("command is empty")
if "/" in program:
filename = program
try:
st = self.config.options.stat(filename)
except OSError:
st = None
else:
path = self.config.get_path()
found = None
st = None
for dir in path:
found = os.path.join(dir, program)
try:
st = self.config.options.stat(found)
except OSError:
pass
else:
break
if st is None:
filename = program
else:
filename = found
# check_execv_args will raise a ProcessException if the execv
# args are bogus, we break it out into a separate options
# method call here only to service unit tests
self.config.options.check_execv_args(filename, commandargs, st)
return filename, commandargs
def get_execv_args(self):
"""Internal: turn a program name into a file name, using $PATH,
make sure it exists / is executable, raising a ProcessException
if not """
try:
commandargs = shlex.split(self.config.command)
except ValueError, e:
raise BadCommand("can't parse command %r: %s" % \
(self.config.command, str(e)))
class Subprocess:
"""A class to manage a subprocess."""
# Initial state; overridden by instance variables
pid = 0 # Subprocess pid; 0 when not running
config = None # ProcessConfig instance
state = None # process state code
listener_state = None # listener state code (if we're an event listener)
event = None # event currently being processed (if we're an event listener)
laststart = 0 # Last time the subprocess was started; 0 if never
laststop = 0 # Last time the subprocess was stopped; 0 if never
delay = 0 # If nonzero, delay starting or killing until this time
administrative_stop = 0 # true if the process has been stopped by an admin
system_stop = 0 # true if the process has been stopped by the system
killing = 0 # flag determining whether we are trying to kill this proc
backoff = 0 # backoff counter (to startretries)
dispatchers = None # asnycore output dispatchers (keyed by fd)
pipes = None # map of channel name to file descriptor #
exitstatus = None # status attached to dead process by finsh()
spawnerr = None # error message attached by spawn() if any
group = None # ProcessGroup instance if process is in the group
def __init__(self, config):
"""Constructor.
Argument is a ProcessConfig instance.
"""
self.config = config
self.dispatchers = {}
self.pipes = {}
self.state = ProcessStates.STOPPED
def removelogs(self):
for dispatcher in self.dispatchers.values():
if hasattr(dispatcher, 'removelogs'):
dispatcher.removelogs()
def reopenlogs(self):
for dispatcher in self.dispatchers.values():
if hasattr(dispatcher, 'reopenlogs'):
dispatcher.reopenlogs()
def drain(self):
for dispatcher in self.dispatchers.values():
# note that we *must* call readable() for every
# dispatcher, as it may have side effects for a given
# dispatcher (eg. call handle_listener_state_change for
# event listener processes)
if dispatcher.readable():
dispatcher.handle_read_event()
if dispatcher.writable():
dispatcher.handle_write_event()
def write(self, chars):
if not self.pid or self.killing:
raise OSError(errno.EPIPE, "Process already closed")
stdin_fd = self.pipes['stdin']
if stdin_fd is None:
raise OSError(errno.EPIPE, "Process has no stdin channel")
dispatcher = self.dispatchers[stdin_fd]
if dispatcher.closed:
raise OSError(errno.EPIPE, "Process' stdin channel is closed")
dispatcher.input_buffer += chars
dispatcher.flush() # this must raise EPIPE if the pipe is closed
def get_execv_args(self):
"""Internal: turn a program name into a file name, using $PATH,
make sure it exists / is executable, raising a ProcessException
if not """
try:
commandargs = shlex.split(self.config.command)
except ValueError, e:
raise BadCommand("can't parse command %r: %s" % \
(self.config.command, str(e)))
if commandargs:
program = commandargs[0]
else:
raise BadCommand("command is empty")
if "/" in program:
filename = program
try:
st = self.config.options.stat(filename)
except OSError:
st = None
else:
path = self.config.options.get_path()
found = None
st = None
for dir in path:
found = os.path.join(dir, program)
try:
st = self.config.options.stat(found)
except OSError:
pass
else:
break
if st is None:
filename = program
else:
filename = found
# check_execv_args will raise a ProcessException if the execv
# args are bogus, we break it out into a separate options
# method call here only to service unit tests
self.config.options.check_execv_args(filename, commandargs, st)
return filename, commandargs
def get_execv_args(self):
# 检查配置文件的执行文件夹，分解执行命令
"""Internal: turn a program name into a file name, using $PATH,
make sure it exists / is executable, raising a ProcessException
if not """
try:
# 分词,按照空格
commandargs = shlex.split(self.config.command)
except ValueError as e:
raise BadCommand("can't parse command %r: %s" % \
(self.config.command, str(e)))
# 执行程序
# file_name ='/home/ejior/anaconda3/envs/web/bin/python3.6'
# os.stat(file_name))
# os.stat_result(st_mode=33277, st_ino=5503447, st_dev=66307, st_nlink=1, st_uid=1000, st_gid=1000,
# st_size=11944432, st_atime=1565227511, st_mtime=1552473391, st_ctime=1552473391)
'''
st_mode: inode 保护模式
st_ino: inode 节点号。
st_dev: inode 驻留的设备。
st_nlink: inode 的链接数。
st_uid: 所有者的用户ID。
st_gid: 所有者的组ID。
st_size: 普通文件以字节为单位的大小；包含等待某些特殊文件的数据。
st_atime: 上次访问的时间。
st_mtime: 最后一次修改的时间。
st_ctime: 由操作系统报告的"ctime"。在某些系统上（如Unix）是最新的元数据更改的时间，在其它系统上（如Windows）
是创建时间（详细信息参见平台的文档）。
'''
if commandargs:
program = commandargs[0]
else:
raise BadCommand("command is empty")
if "/" in program:
filename = program
try:
st = self.config.options.stat(filename)
except OSError:
st = None
else:
# 从各个bin目录中寻找该程序
path = self.config.get_path()
found = None
st = None
for dir in path:
found = os.path.join(dir, program)
try:
st = self.config.options.stat(found)
except OSError:
pass
else:
break
if st is None:
filename = program
else:
filename = found
# check_execv_args will raise a ProcessException if the execv
# args are bogus, we break it out into a separate options
# method call here only to service unit tests
# filename的绝对路径
self.config.options.check_execv_args(filename, commandargs, st)
return filename, commandargs